Optical connector apparatus

ABSTRACT

An optical connector apparatus includes a connector which is connected to an electro-optical composite cable including an optical fiber and a metal conductor, and a connection object to be connected. The connector is provided with a ferrule which has a conductive portion on at least a part of the surface thereof. The connection object to be connected is provided with an electrically conductive connection member to be connected to the ferrule. The ferrule and the cable are connected by a crimping structure. When the ferrule is inserted in the connection member, the connector and the connection object to be connected are electrically and optically connected to each other. Provided is also an optical connector apparatus which comprises a connector having a plurality of ferrules having distances between the end of the ferrules and the conductive portions so that the timing of the connection of the connector to the object to be connected is delayed, and thus the optical connector apparatus is capable of hot swapping. The connection object to be connected can be a combination of an adapter and a mating connector, or an optical element and an adapter which holds the same, etc.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Divisional of U.S. Ser. No. 13/147,888, filed Aug.4, 2011, which is a U.S. National Phase Application under 35 USC 371 ofInternational Application No. PCT/JP2010/051496 filed Feb. 3, 2010, theentire contents of both of which are incorporated herein by reference.

TECHNICAL FIELD

This invention relates to an optical connector apparatus, and especiallyto an optical connector apparatus comprising: a wiring structure for anelectro-optical composite cable and a ferrule, a connector connectedwith the electro-optical composite cable, and an adaptor relaying aconnection between the connector and a connection object (a matingconnector, an optical element, or the like).

BACKGROUND ART

A wiring structure for an electro-optical composite cable and a ferruleis disclosed in, for example, Patent Document 1 to Patent Document 3.The wiring structures disclosed in them are as follows. First, a tubularmember integrally formed with (or prepared separately from) the ferruleis inserted between an optical fiber strand and a tensile-strengthresistant fiber. Next, the ferrule is crimped so that thetensile-strength resistant fiber and an outer jacket are interposedbetween the ferrule and the tubular member. Thus, the electro-opticalcomposite cable is connected with the ferrule without using an adhesiveagent or the like.

A split sleeve (a sleeve having a cut portion) is known as a connectionmember connected with the ferrule. Techniques which solve a problem ofthe split sleeve are disclosed in Patent Document 4 to Patent Document6. Each of the connection members disclosed in them is not provided withthe cut portion. The connection member is configured to support theferrule at three points (surfaces). Patent Document 7 discloses animproved technique of Patent Document 4.

Patent Document 8 discloses one of the examples of connectors and anadaptor wherein each of the connectors is connected with anelectro-optical composite cable, and the adaptor connects the connectorswith each other. The disclosed connector comprises a conductive ferruleholding an optical fiber included in the electro-optical composite cablewhile connected with a metal conductive material of the electro-opticalcomposite cable. The adaptor is made of a synthetic resin. A conductiveconnection member adjusting a position of an axis of the ferrule isformed in the adaptor by insert molding. An electrical connectionbetween the ferrules is carried out as follows. First, each ferrule oftwo connectors is inserted into the connection member. Then, endsurfaces of the ferrules are brought into contact with each other withinthe connection member.

A technique relating to hot swapping of the electrical connector isdisclosed in, for example, Patent Document 9. The disclosed electricalconnector uses contacts each of which has a projection length from theconnector wherein the projection lengths are different from each otherso that a timing of connection can be shifted for every contact. Theabove-described structure enables the hot swapping.

Patent Document 1:JPA 2004-191397

Patent Document 2:JPA 2006-146084

Patent Document 3:JPA 2006-84788

Patent Document 4:JPA H10-31134

Patent Document 5:JPA S59-204814

Patent Document 6:JPA H5-164941

Patent Document 7:JPA 2006-23420

Patent Document 8:JPA S62-19813

Patent Document 9:JPA H6-5153

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

Applying the above crimping structure for an electrical connectionbetween a metal conductor of an electro-optical composite cable and aconductive ferrule may be cause a problem that connection strength maybe weak. It is therefore an object of the present invention to identifyand eliminate a cause which brings a reduction of the connectionstrength in a wiring structure between the electro-optical compositecable and the conductive ferrule and to provide the wiring structurehaving high connection strength.

Each of the sleeves disclosed in Patent Document 4 to Patent Document 7has a high spring constant so that there is a possibility that theferrule may be damaged when the ferrule is inserted into the sleeve.Another problem is that a manufacturing cost may be high because highprecision is required for holding the ferrule appropriately. It istherefore another object of the present invention to provide an opticalconnector apparatus which comprises sleeve which is of a low cost andwhich can hold the ferrule appropriately without giving damage thereto.

Furthermore, as for one of methods for holding an optical fiber by theferrule, there is a method using an adhesive agent. In this method,general techniques to remove an adhesive agent leaked from an endsurface of the ferrule are to polish, the end surface of the ferrule.However, in a case that the ferrule has conductivity on its surface, theconductivity may be lost when the ferrule is polished. For this reason,when the polished end surfaces of the ferrules are brought into contactwith each other, there is a possibility that a good electricalconnection may not be obtained between them.

In addition, the sleeve included in an adaptor of Patent Document 1 isgenerally made of conductive material so that the sleeve has apossibility to contribute to the electrical connection between theferrules. However, the sleeve does not assure the electrical connectionbetween the ferrules, in a case where, for example the ferrules areslightly uneven in size. This is because a principal object of thesleeve is to adjust axes of the ferrules as clearly understood from afact that the sleeve is formed into the adaptor by insert molding sothat the sleeve is prevented from being moved and/or displaced withinthe adaptor. Accordingly, a connection simply between conductiveferrules may cause the contact therebetween be unstable. In addition,when the conductive ferrule is used, foreign matter may be attachedthereto so that an electrical short may occur, and the ferrule may beaccidentally touched by a finger because an end of the ferrule isprojected from a housing of the connector.

It is therefore another object of the present invention to provide anoptical connector apparatus which has a structure that ensures theelectrical connection between the ferrules. It is also another object toprovide the optical connector apparatus which prevents the electricalshort or the like caused by a touch by a finger or attachment of foreignmatter, and so on to the end portion of the ferrule.

Furthermore, it is another object of the present invention to provide anoptical connector and an optical connector apparatus using the samewhich enables, in addition to an optical connection, an electricalconnection and hot swapping by using a new method distinct from PatentDocument 9.

Means for Solving the Problems

One aspect of the present invention provides an optical connectorapparatus comprising: a first connector connected with a firstelectro-optical composite cable including a first optical fiber and afirst metal conductor; a second connector connected with a secondelectro-optical composite cable including a second optical fiber and asecond metal conductor; and an adaptor relaying a connection between thefirst connector and the second connector. The first connector comprisesa first ferrule holding the first optical fiber, at least a part of asurface of the first ferrule having a conductive portion electricallyconnected with the first metal conductor. The second connector comprisesa second ferrule holding the second optical fiber, at least a part of asurface of the second ferrule having a conductive portion electricallyconnected with the second metal conductor. The adaptor comprises aconnection member holding the first ferrule and the second ferrule, atleast a part of a surface of the adaptor having conductivity for makingan electrical connection between the conductive portion of the firstferrule and the conductive portion of the second ferrule.

Another aspect of the present invention provides an optical connectorapparatus comprising: an optical element; a ferrule holding an opticalfiber of an electro-optical composite cable and having a conductiveportion electrically connected with a metal conductor of theelectro-optical composite cable; and an adaptor holding the opticalelement and relaying a connection between the ferrule and the opticalelement. The adaptor comprises a connection member holding the ferrule,at least a part of a surface of the connection member havingconductivity for making an electrical connection with the conductiveportion.

Another aspect of the present invention provides an optical connectorapparatus comprising: a ferrule holding an optical fiber of anelectro-optical composite cable and having a contact portionelectrically connected with a metal conductor of the electro-opticalcomposite cable; and a connection object making an optical connectionand an electrical connection simultaneously with the ferrule. Theconnection object comprises: a receiving portion receiving an endportion of the ferrule; a conductive portion provided on at least theend portion of the receiving portion; and an optical connection portionprovided inside the receiving portion. The end portion of the ferrule isreceived in the receiving portion so that the optical connection is madeby facing an end surface of the optical fiber toward the opticalconnection portion while the electrical connection is made by contactingthe contact portion to the conductive portion.

Another aspect of the present invention provides an optical connectorapparatus comprising: a first connector connected with a firstelectro-optical composite cable including a first optical fiber and afirst metal conductor; a second connector connected with a secondelectro-optical composite cable including a second optical fiber and asecond metal conductor; and an adaptor and relaying a connection betweenthe first connector and the second connector. The first connectorcomprises a first ferrule holding the first optical fiber, at least apart of a surface of the first ferrule having a first conductiveportion, the first conductive portion being connected with the firstmetal conductor. On the other hand, the second connector comprises asecond ferrule holding the second optical fiber, at least a part of thesecond ferrule having a second conductive portion, the second conductiveportion being connected with the second metal conductor. The adaptorcomprises a connection member which connects the first ferrule with thesecond ferrule. An end portion of the first ferrule is provided with arecess portion, and an end of the first optical fiber is positionedwithin the recess portion so as not to project from an end surface ofthe first ferrule.

Another aspect of the present invention provides an optical connectorapparatus having a connection member connecting ferrules, wherein theconnection member is formed by processing a metal sheet having two edgeportions so that the connection member has a main body having a tube ora cylinder shape, the two edge portions facing each other. The main bodyportion comprises a plurality of ferrule-contact portions, each of theferrule-contact portions being separated from each other on aperpendicular surface perpendicular to an axis-direction of theconnection member and being brought into contact with the ferrule whenthe connection member holds the ferrule.

Another aspect of the present invention provides an optical connectorcomprising a first ferrule having a first end surface and a secondferrule having a second end surface. The first ferrule is provided witha first conductive portion. The second ferrule is provided with a secondconductive portion. A distance between the first end surface and thefirst conductive portion is different from another distance between thesecond end surface and the second conductive portion.

Effect of Invention

According to the present invention, with the above wiring methods, thecrimped portion is crimped in a state that size difference between themetal conductor and the outer jacket is adjusted by an adjuster portionso that the connection strength can be stable. The crimped portion hasno unnecessary clearance so that there is another advantageous thatsimple jig may be used for crimping.

According to the present invention, the connection member (the splitsleeve) is configured to hold the first ferrule and the second ferrulefrom outside in a diameter direction so that an electrical connectionbetween the first ferrule and the second ferrule is reliable even when apolishing process is carried out for each ferrule.

According to the present invention, the sleeve is formed by processing ametal sheet having two edge portions so that the sleeve has a main bodyhaving a tube or a cylinder shape wherein the two edge portions face (orjoin to) each other. For this reason, the spring constant can bedecreased, and the ferrules are held appropriately. The opposed-edgesportion (joint portion) is formed on the sleeve, and the ferrule is heldby three ferrule-contact portions formed by the process. Therefore, amanufacturing cost can be reduced.

According to the present invention, a plurality of the ferrules areprovided in the optical connector, wherein each of the ferrules has alength between an end surface of the ferrule and the conductive portionto be connected with the mating connector or the like, and the lengthsof the ferrules are different from each other. Therefore, the electricalconnection is reliably established when the optical connection with themating connector or the like is established, in addition, hot swappingis usable.

BRIEF DESCRIPTION OF DRAWINGS

[FIG. 1] An oblique view showing an optical connector apparatusaccording to a first embodiment of the present invention. Theillustrated optical connector apparatus comprising connectors (a firstconnector and a second connector) and an adaptor is in a separatedstate.

[FIG. 2] An exploded oblique view showing the optical connectorapparatus of FIG. 1.

[FIG. 3] A cross-sectional view showing the optical connector apparatusof FIG. 1, taken along lines III-III. The illustrated optical connectorapparatus is in a connection state.

[FIG. 4] A cross-sectional view showing a wiring structure between anelectro-optical composite cable and a ferrule according to a firstwiring method of the present invention.

[FIG. 5] A partially-cutaway cross-sectional view showing procedures ofmaking the wiring structure of FIG. 4.

[FIG. 6] An oblique view showing a structure of an electro-opticalcomposite cable according to the embodiment of the present invention.Each part of the electro-optical composite cable is shown exposed foreasy understanding.

[FIG. 7] A cross-sectional view showing the electro-optical compositecable of FIG. 6.

[FIG. 8] A cross-sectional view showing a wiring structure between anelectro-optical composite cable and a ferrule according to a secondwiring structure of the present invention.

[FIG. 9] An oblique view showing procedures of making the wiringstructure of FIG. 8.

[FIG. 10] A cross-sectional view showing a wiring structure between anelectro-optical composite cable and a ferrule according to a thirdwiring method of the present invention.

[FIG. 11] An oblique view showing procedures of making the wiringstructure of FIG. 10.

[FIG. 12] A cross-sectional view showing a wiring structure between anelectro-optical composite cable and a ferrule according to a fourthwiring method of the present invention.

[FIG. 13] An oblique view showing procedures of making the wiringstructure of FIG. 12.

[FIG. 14] An enlarged cross-sectional view of the optical connectorapparatus of FIG. 3 showing a connection member and its vicinity whereinthe connection member is included in an adaptor.

[FIG. 15] A cross-sectional view showing only the connector (the firstconnector) included in the optical connector apparatus of FIG. 3.

[FIG. 16] A cross-sectional view showing a variation example of theferrule (composite type).

[FIG. 17] An oblique view showing the ferrule of FIG. 16.

[FIG. 18] A view showing a variation example of an adaptor used for theconnector of FIG. 1.

[FIG. 19] A cross-sectional view showing an optical connector apparatuscomposing of the ferrules illustrated in FIG. 16 and FIG. 17, theadaptors illustrated in FIG. 18 and the connection member illustrated inFIG. 20. The illustrated optical connector apparatus is in theconnection state.

[FIG. 20] A view showing a connection member (variation example 1) usedfor the optical connector apparatus of FIG. 19.

[FIG. 21] A view showing another type of a connection member (variationexample 2) to be used instead of the connection member of FIG. 1.

[FIG. 22] An oblique view showing an optical connector apparatus usingother types of the connection member. The connectors and the adaptorincluded in the illustrated connector apparatus are in a separatedstate.

[FIG. 23] An exploded oblique view showing the connector of FIG. 22.

[FIG. 24] A cross-sectional view showing the optical connector of FIG.22, taken along lines XXIV-XXIV. The illustrated optical connectorapparatus is in the connection state.

[FIG. 25] A top view showing the connector of FIG. 22.

[FIG. 26] A front view showing the connector of FIG. 22.

[FIG. 27] A cross-sectional view showing the adaptor of FIG. 26, takenalong lines XXVII-XXVII.

[FIG. 28] A cross-sectional view showing the connection member(variation example 3) included in the adaptor of FIG. 23.

[FIG. 29] A front view showing the connection member of FIG. 28. Aninscribed circle and a circumscribed circle are also illustrated.

[FIG. 30] A cross-sectional view showing the adaptor of FIG. 25, takenalong lines XXX-XXX.

[FIG. 31] A cross-sectional view of an adaptor of FIG. 27 in a casewhere the connection member (variation example 4) of FIG. 33 is applied.

[FIG. 32] An oblique view showing the connection member included in theadaptor of FIG. 31.

[FIG. 33] A front view showing the connection member of FIG. 32.

[FIG. 34] A partially-cutaway internal side view showing an opticalconnector apparatus according to a second embodiment of the presentinvention. In the illustration, only a housing is illustrated in crosssection.

[FIG. 35] An oblique view showing an adaptor used for an opticalconnector apparatus according to a third embodiment of the presentinvention. The adaptor holds a connection member.

[FIG. 36] An oblique view showing the connection member held by theadaptor of FIG. 35.

[FIG. 37] A cross-sectional view showing the adaptor of FIG. 35, takenalong lines XXXVII-XXXVII. An illustration of an optical element isomitted.

[FIG. 38] An oblique view showing a connection object (an adaptor and aconnector (a second connector)) included in an optical connectorapparatus according to a fourth embodiment of the present invention. Theillustrated optical connector apparatus is in the connection state.

[FIG. 39] A cross-sectional view showing a ferrule (an insulation type)included in the optical connector apparatus of FIG. 38.

[FIG. 40] An oblique view showing the ferrule of FIG. 39.

[FIG. 41] An oblique view showing the adaptor included in the opticalconnector apparatus of FIG. 38.

[FIG. 42] An oblique view showing a connection member (contact type)included in the adaptor of FIG. 41.

[FIG. 43] An oblique view showing an adaptor used for an opticalconnector apparatus according to a fifth embodiment of the presentinvention. The adaptor holds a connection member.

[FIG. 44] An oblique view showing the connection member held by theadaptor of FIG. 43.

[FIG. 45] A cross-sectional view showing the adaptor of FIG. 43, takenalong lines XLV-XLV. An illustration of an optical element is omitted.

[FIG. 46] An oblique view showing an adaptor used for an opticalconnector apparatus according to a sixth embodiment of the presentinvention. Connectors (a first connector and a second connector) and anadaptor which constitutes the optical connector apparatus are in anunconnected state.

[FIG. 47] An exploded oblique view showing the optical connectorapparatus of FIG. 46.

[FIG. 48] A cross-sectional view showing the optical connector apparatusof FIG. 46, taken along lines XLVIII-XLVIII.

[FIG. 49] A cross-sectional view showing the optical connector apparatusof FIG. 46, taken along lines IL-IL.

[FIG. 50] A top view showing the adaptor of FIG. 46.

[FIG. 51] A front view showing the adaptor of FIG. 46.

[FIG. 52] a cross-sectional view showing the adaptor of FIG. 50, takenalong lines LII-LII.

[FIG. 53] A cross-sectional view showing the adaptor of FIG. 51, takenalong lines LIII-LIII.

[FIG. 54] An oblique view showing an adaptor used for an opticalconnector apparatus according to a eighth embodiment of the presentinvention.

[FIG. 55] An oblique view showing a variation example of an end portionof the ferrule.

[FIG. 56] A side view showing a connection between the ferrule of FIG.54 and a normal ferrule.

BEST MODE FOR CARRYING OUT THE INVENTION

A brief explanation will be made about components of an opticalconnector apparatus according to an embodiment of the present invention.The optical connector apparatus comprises a connector and an adaptor,wherein the connector is connected with an electro-optical cable, andthe adaptor relays between the connector and a connection object. Theconnector comprises a ferrule connected with an electro-opticalcomposite cable. The adaptor comprises a connection member. Anelectro-optical connection between the connector and the adaptor is madeby connecting the ferrule of the connector to the connection member ofthe adaptor.

The explanation will be made about the connection object, taking amating connector or a connector comprising an optical element as anexample. A combination of the adaptor and the mating connector or acombination of adaptor and the connector comprising the optical elementmay be considered as one connection object. With reference to thedrawings, a detailed explanation will be made hereinbelow about theoptical connector applicable for the electro-optical composite cableaccording to the embodiment.

First Embodiment

In an optical connector according to a first embodiment of the presentinvention, a ferrule is gripped by a connection member so that aconnection between them is made. An explanation of the first embodimentwill be made about two connectors and an adaptor relaying between them.As illustrated in FIGS. 1 to 3, the optical connector 10 comprises afirst connector 200 connected with a first electro-optical compositecable 100, a second connector 200′ connected with a secondelectro-optical composite cable 100′, and an adaptor 500 relaying aconnection between the first connector 200 and the second connector200′.

As illustrated in FIG. 3, the first connector 200 comprises a firstferrule 220. The first ferrule 220 is connected with the firstelectro-optical composite cable 100. The second connector 200′ comprisesa second ferrule 220′. The second ferrule 220′ is connected with thesecond electro-optical composite cable 100′. A first to fourth wiringstructures illustrated in FIGS. 4 to 13 may be used as a wiringstructure between the first electro-optical composite cable 100 and thefirst ferrule 220 (or a wiring structure between the secondelectro-optical composite cable 100′ and the second ferrule 220′) asappropriate.

As illustrated in FIGS. 4 and 5, The first wiring structure comprise anelectro-optical composite cable 100, a ferrule 2200 a made of conductivematerial such as metal, and a sleeve 240 made of conductive materialsuch as metal. Except for metal, conductive resin or insulation resinformed with a metal thin layer on a surface may be used as theconductive material.

As illustrated in FIGS. 6 and 7, the electro-optical composite cable 100comprises an optical fiber strand 121 composed of an optical fiber 110and a protection cover covering the optical fiber 110, a metal conductor130 positioned on an outer circumference of the optical fiber strand 121and constituting a pipe-shaped outer conductor by disposing a pluralityof metal wires without gaps therebetween, and an outer jacket 140covering them. The outer jacket 140 of the present embodiment is made ofpolyvinyl chloride. In addition, as illustrated in FIG. 6, theelectro-optical composite cable 100 further comprises a tensile-strengthfiber 122 provided between the optical fiber strand 121 and the metalconductor 130.

On the other hand, as illustrated in FIG. 4, he ferrule 2200 a comprisesa main body portion 210 and a wiring portion 211 positioned at a back ofthe main body portion 210. The main body portion 210 is inserted withthe optical fiber strand 121 and holds the inserted optical fiber strand121 in a center part. On the other hand, wiring portion 211 functions asa portion to be wired with the electro-optical composite cable 100(especially, metal conductor 130). In detail, a holding hole is formedat a back end of the ferrule 2200 a (i.e. back end of wiring portion211) and the main body portion 210, wherein the holding hole has aninner diameter substantially equal to an outer diameter of the opticalfiber strand 121. Moreover, the main body portion 210 is formed with acommunication hole which communicates the holding hole with a front endof the ferrule 2200 a (i.e. front end of the main body portion 210),wherein the communication hole has a diameter substantially equal tothat of the optical fiber 110. The communication hole is provided on acenter part of the main body portion 210 in a diameter direction.

As illustrated in FIG. 4, the wiring portion 211 of the ferrule 2200 acomprises a tubular portion 212 extending toward the back end and aring-like recess 232 receiving the sleeve 240. The tubular portion 212of the present embodiment has an inner diameter substantially equal tothe outer diameter of the optical fiber strand 121 has a thickness andsubstantially equal to a thickness of the outer jacket 140 of theelectro-optical composite cable 100. The ring-like recess 232 has anL-like shape in cross-section. The L-like shape extends toward the backend of the ferrule 2200 a, wherein the L-like shape specificallyprojects outward from the tubular portion 212 in the diameter directionand in parallel with the tubular portion 212. The maximum inner diameterof the ring-like recess 232 of the present embodiment is substantiallyequal to the outer diameter of the sleeve 240.

In the present embodiment, a connection is carried out between theelectro-optical composite cable 100 and the ferrule 2200 a with thesleeve 240 as illustrated in FIG. 5.

As illustrated in FIG. 5( a), the outer jacket 140 of theelectro-optical composite cable 100 is removed so that the metalconductor 130 is bared (exposed). Moreover, an unnecessary metalconductor 130 is removed so that the optical fiber strand is bared(exposed). In addition, the protection cover 120 is removed in the frontend of the optical fiber strand 121 so that the optical fiber 110 isbared (exposed). The electro-optical composite cable 100 is insertedinto the sleeve 240. In other words, the sleeve 240 is positioned at aback of the bared metal conductor 130 and on the outer jacket 140. Themetal conductor 130 is once folded up and then returned back for thenext step so that the metal conductor 130 is slightly apart from theoptical fiber strand 121. As understood from FIG. 6, in the presentembodiment, a length of an exposed portion (bared portion) of the metalconductor 130 is substantially equal to a length of the tubular portionin an axis direction.

Next, adhesive agent is applied on an outer circumference of theprotection cover 120 (outer circumference of the optical fiber strand121), and the optical fiber strand 121 is inserted into the ferrule 2200a as illustrated in FIG. 5( b). With these steps, the electro-opticalcomposite cable 100 (optical fiber strand 121) is adhered to the ferrule2200 a. In this step, the metal conductor 130 is arranged on an outercircumference of the tubular portion 212.

Next, the sleeve is slid toward the front end of the ferrule 2200 a sothat a front end of the sleeve 240 is brought into contact with thering-like recess 232. With this step, the sleeve 240 is electricallyconnected with the ferrule 2200 a. In the sleeve 240, the tubularportion 212 having a thickness substantially equal to that of outerjacket 140 is inserted inside of the bared metal conductor 130.Therefore, the size difference between the outer circumference of themetal conductor 130 and the outer circumference of the outer jacket 140is adjusted. In other words, the tubular portion 212 functions as theadjuster portion.

The sleeve 240 is crimped in a state where the adjuster portion adjuststhe size difference so as to carry out the connection between the metalconductor 130 and ferrule 2200 a. As is clear from the case above, thesleeve 240 of the present embodiment functions as a crimped portion.After the sleeve 240 is crimped, the adhesive agent is dried by heating.In a final step, the optical fiber 110 is polished. The connectionbetween the electro-optical composite cable 100 and the ferrule 2200 ais completed.

As described above, in the sleeve 240 of the crimped portion, the sizedifference does not exist between the outer circumference of the metalconductor 130 and the outer circumference of the outer jacket 140because of a presence of the tubular portion 212. Therefore, there is noundesired clearance inside the sleeve 240. The crimped portion has asimple shape so that a crimped sleeve has also a simple shape.Therefore, high connection strength can be obtained.

As a second wiring structure, a wiring structure as illustrated in FIG.8 and FIG. 9 will be explained. Upon explaining the present, the samereference numerals are given to the components similar to theabove-described first structure and, therefore, the description of thosecomponents will be omitted.

The second wiring structure is different from the first wiring structurein that the second wiring structure does not have the sleeve. However,as described below, the second wiring structure comprises a part whichfunctions as the crimped portion and the adjuster portion. In thispoint, the second wiring structure is similar to the first wiringstructure.

As illustrated in FIG. 8, the ferrule 2200 b comprises a main bodyportion 210 a and a wiring portion 211 a. The main body portion 210 acomprises a structure similar to the main body portion 210 (see FIG. 4)of the first wiring structure. The wiring portion 211 a comprises afirst tubular portion 212 a extending backward from the main bodyportion 210 a and a second tubular portion 226 a further extendingbackward from the first tubular portion 212 a.

The first tubular portion 212 a has a first inner radius correspondingto a length between the center part of the electro-optical compositecable 100 and an outer circumference of the metal conductor 130. Thesecond tubular portion 226 a has a second inner radius corresponding toa length between the center part of the electro-optical composite cable100 and an outer circumference of the outer jacket 140 (outer radius ofthe outer jacket 140). Outer radiuses of the first tubular portion 212 aand the second tubular portion 226 a are equal to each other. Therefore,an exterior of the wiring portion 211 a has a tubular shape which has nosize difference while an interior of the wiring portion 211 a has thesize difference between the first tubular portion 212 a and the secondtubular portion 226 a. As is clear from a difference between the firstinner radius and the second inner radius, a size of the size differencebetween the first tubular portion 212 a and the second tubular portion226 a of the present wiring structure is substantially equal to athickness of the outer jacket 140.

In the present wiring structure, the connection between theabove-described ferrule 2200 b and the electro-optical composite cable100 is carried out as illustrated in FIG. 9.

Similarly to a first wiring method, the outer jacket 140 of theelectro-optical composite cable 100 is removed so that the metalconductor 130 is bared. Next, an unnecessary metal conductor 130 isremoved so that the optical fiber strand 121 is bared. In addition, theprotection cover 120 is removed in the front end of the optical fiberstrand 121 so that optical fiber 110 is bared (see FIG. 9( a)).

Next, the adhesive agent is applied on an outer circumference of theprotection cover 120 (an outer circumference of the optical fiber strand121) and the optical fiber strand 121 is inserted into the ferrule 2200b as illustrated in FIG. 9( b) so that the electro-optical compositecable 100 (optical fiber strand 121) is adhered to the ferrule 2200 a.Here in, a size of the front end surface of the metal conductor 130corresponds to a size of the back end surface of the first tubularportion 212 a. Therefore, there is no undesired clearance in the wiringportion 211 a. Then, after, the wiring portion 211 a is crimped toconnect the metal conductor 130 and the wiring portion 211 a (ferrule2200 b), the adhesive agent is dried by heating. In the final step, theoptical fiber 110 is polished. Thus, the connection of theelectro-optical composite cable 100 and the ferrule 2200 a is completed.

As is understood from the above explanation, the wiring portion 211 a ofthe present wiring structure is constituted by integrally forming thecrimped portion and the adjuster portion. Specifically, the wiringportion 211 a may be divided to the first tubular portion 212 a and thesecond tubular portion 226 a in the axis direction while the wiringportion 211 a may be divided to the adjuster portion and the crimpedportion, in this order from inside, in a radius direction. In otherwords, the first tubular portion 212 a has functions of the adjusterportion and the crimped portion while the second tubular portion 226 ahas only the function of the crimped portion. A shape of the crimpedwiring portion 211 a may be made simple because the wiring portion 211 ahaving the above structure enables to eliminate the undesired clearancein the wiring portion 211 a. Therefore, high connection strength can beobtained.

As a third wiring structure, the wiring structure illustrated in FIG. 10and FIG. 11 will be explained. Upon explaining the present, the samereference numerals are given to the components similar to theabove-described first structure and, therefore, the description of thosecomponents will be omitted.

As illustrated in FIG. 10, a ferrule 2200 c comprises a main bodyportion 210 b and a wiring portion 211 b. The main body portion 210 bcomprises a structure similar to the main body portion 210 (see FIG. 4)of the first wiring structure. The wiring portion 211 b has a tubularshape extending backward and has an inner diameter substantially thesame as the outer diameter of the outer jacket 140 of theelectro-optical composite cable 100.

In addition, as illustrated in FIG. 10, the present wiring structurecomprises a sleeve 240 b. An inner diameter of the sleeve 240 b issubstantially equal to a predetermined diameter (which is defined as anouter diameter of the metal conductor 130) wherein the predetermineddiameter is twice the radius corresponding to a length between thecenter part of the electro-optical composite cable 100 and the outercircumference of the metal conductor 130. An outer diameter of thesleeve 240 b is substantially equal to the outer diameter of the outerjacket 140. In other words, a thickness of the sleeve 240 b issubstantially equal to a thickness of the outer jacket 140.

In the present embodiment, the above-described ferrule 2200 c and thesleeve 240 b are connected with the electro-optical composite cable 100as illustrated in FIG. 11.

Similarly to the first wiring structure, the outer jacket 140 of theelectro-optical composite cable 100 is removed so that the metalconductor 130 is bared. Next, the unnecessary metal conductor 130 isremoved so that the optical fiber strand 121 is bared. In addition, theprotection cover 120 is removed in the front end of the optical fiberstrand 121 so that optical fiber 110 is bared (see FIG. 11( a)). Asunderstood from FIG. 10, a length of an exposed portion (a baredportion) is substantially equal to a length of the sleeve 240 b in theaxis direction.

Next, as illustrated in FIG. 11( b), the sleeve 240 b is inserted withthe electro-optical composite cable 100. The metal conductor 130 iscovered with the sleeve 240 b so that a size difference between themetal conductor 130 and the outer jacket 140 is adjusted. In otherwords, in the present embodiment, the sleeve 240 b functions as theadjuster portion which adjusts the size difference between metalconductor 130 and the outer jacket 140.

Afterwards, the adhesive agent is applied on an outer circumference ofthe protection cover 120 (an outer circumference of the optical fiberstrand 121), and the optical fiber strand 121 is inserted into theferrule 2200 c as illustrated in FIG. 11( c). Thus, the electro-opticalcomposite cable 100 (the optical fiber strand 121) is adhered to theferrule 2200 c. Then after, the wiring portion 211 b is crimped toconnect the metal conductor 130 and the wiring portion 211 b (theferrule 2200 c) , the adhesive agent is dried by heating. In the finalstep, the optical fiber 110 is polished. Thus the connection between theelectro-optical composite cable 100 and the ferrule 2200 c is completed.As is understood from the above, the wiring portion 211 b of the presentembodiment functions as the crimped portion.

As described above, in the wiring portion 211 b which functions as thecrimped portion, by presence of the sleeve 240 b, the size differencebetween the metal conductor 130 and the outer jacket 140 is adjusted sothat there is no undesired clearance or the like in the wiring portion211 b. A shape of the crimped wiring portion 211 b may be made simple sothat high connection strength can be obtained.

As a fourth wiring structure, the wiring structure illustrated in FIG.12 and FIG. 13 will be explained. Upon explaining the present, the samereference numerals are given to the components similar to theabove-described first structure and, therefore, the description of thosecomponents will be omitted.

As illustrated in FIG. 12, the ferrule 2200 d comprises a main bodyportion 210 c and a wiring portion 211 c. The main body portion 210 ccomprises a structure similar to the main body portion 210 (see FIG. 4)according to the first wiring structure. The wiring portion 211 caccording to the present wiring structure has a tubular shape extendingbackward and is similar to the above-described wiring portion 211 baccording to the third wiring structure. An inner diameter of the wiringportion 211 c is substantially equal to the outer diameter of the outerjacket 140 of the electro-optical composite cable 100.

In addition, as illustrated in FIG. 12, the present wiring structurecomprises a sleeve 240 c. An inner diameter of the sleeve 240 c issubstantially equal to an outer diameter of the optical fiber strand121. A thickness of the sleeve 240 c is substantially equal to athickness of the outer jacket 140.

In the present wiring structure, the above-described ferrule 2200 d andthe sleeve 240 c are connected with the electro-optical composite cable100 as illustrated in FIG. 13.

Similarly to the first wiring structure, the outer jacket 140 of theelectro-optical composite cable 100 is removed so that the metalconductor 130 is bared. Next, the unnecessary metal conductor 130 isremoved so that the optical fiber strand 121 is bared. In addition, theprotection cover 120 is removed in the front end of the optical fiberstrand 121 so that optical fiber 110 is bared (see FIG. 13( a)). As isunderstood from FIG. 13, a length of an exposed portion (a baredportion) is substantially equal to a length of the sleeve 240 c in theaxis direction.

Next, as illustrated in FIG. 13( b), the sleeve 240 b is inserted withthe electro-optical composite cable 100 so that a size differencebetween the metal conductor 130 and the outer jacket 140 is adjusted. Inother words, even if a size of the sleeve 240 c according to the presentwiring structure is different from a size of the sleeve 240 b accordingto the third wiring structure (see FIG. 10), similarly to the thirdwiring structure, the sleeve 240 c functions as the adjuster portionwhich adjusts the size difference between the metal conductor 130 andthe outer jacket 140.

Next, adhesive agent is applied on an outer circumference of theprotection cover 120 (an outer circumference of the optical fiber strand121), and the optical fiber strand 121 is inserted into the ferrule 2200d as illustrated in FIG. 13(c) so that the electro-optical compositecable 100 (the optical fiber strand 121) is adhered to the ferrule 2200d. Then, after the wiring portion 211 c is crimped to connect the metalconductor 130 with the wiring portion 211 c (ferrule 2200 d), theadhesive agent is dried by heating. In the final step, the optical fiber110 is polished. Thus the connection between the electro-opticalcomposite cable 100 and the ferrule 2200 d is completed. As isunderstood from the above, the wiring portion 211 c of the presentembodiment functions as the crimped portion.

As described above, in the wiring portion 211 c of the crimped portion,by the presence of the sleeve 240 c, the size difference between themetal conductor 130 and the outer jacket 140 is adjusted so that thereis no undesired clearance in the wiring portion 211 c. A shape of thecrimped wiring portion 211 c may be made simple so that high connectionstrength can be obtained.

The concrete explanation has been made about the first to the fourthwiring structures as a wiring structure used in the embodimentsaccording to the present invention. However, the present invention isnot limited thereto. For example, in the first wiring structure or thefourth wiring structure, under the condition such that the metalconductor is deformed (a thickness of the electro-optical compositecable is decreased in the diameter direction) by inserting the tubularportion or the sleeve to the inside of the metal conductor, a thicknessof the tubular portion or the sleeve may be slightly thicker than athickness of the outer jacket in consideration of the decrease of thethickness. The wiring structure between the electro-optical compositecable and the ferrule relating to the present invention and the wiringmethod connecting the electro-optical composite cable with the ferrulemay be applied to all electro-optical composite cable which uses aferrule.

By employing the above-described configuration for the connection, anelectro-optical composite connector can be constituted to have a sizesame as a conventional connector for an optical fiber cable. In otherwords, when the connector of the present embodiment is employed, theelectric wiring may also be laid out within a space which was used foran optical wiring in an apparatus. Therefore, the apparatus may have aspace-saving configuration.

With reference to FIGS. 1 to 3, FIG. 14 and FIG. 15, returning to theexplanation of the optical connector according to the first embodiment,the first electro-optical composite cable 100 and the first ferrule 220(or the second electro-optical composite cable 100′ and the secondferrule 220′) of the first embodiment is wired by the above-describedfirst wiring structure.

As illustrate in FIG. 2, the first connector 200 comprises a firstconnector housing 202 made of insulative material, a first ferrule 220,a first sleeve (a first crimped portion 240), a first bias member 206and a first cable stopper 207 made of insulative material. Asillustrated in FIG. 1, the first connector housing 202 has a lockportion 204 (will be described later) to be locked with the adaptor 500and a lock release member 205 for operating the lock portion 204.

The entire surface of the first ferrule 220 is made of conductivematerials (hereafter, the ferrule of this type is called “a metaltype”). In detail, a base material of the first ferrule 220 is made ofcopper, and nickel-plate and gold-plate are applied thereon. The firstferrule 220 may be made of other member. However, at least a surface isrequired to have conductivity in order to make an electrical connectionwith the first conductor 130. For example, the ferrule may beconstituted by forming the base member with resin, followed by platingthe surface with metal. However, in the present embodiment, as mentionedabove, a crimping process is used for a connection with theelectro-optical composite cable 100 (see FIG. 5). It is thereforepreferable that the base member of the first ferrule 220 is made ofcopper (metal).

As illustrated in FIG. 15, the first ferrule 220 comprises a connectedportion 221 including an end surface 225 of the first ferrule 220 andbeing connected with and held by a connection portion 520 of the adaptor500 (mentioned later), a large diameter portion 228 having a diameterlarger than the connected portion 221, a shoulder portion 230 having adiameter larger than the large diameter portion 228, and a tubularportion (a first adjuster portion) 212 extending backward from theshoulder portion 230. The first ferrule 220 is held by the firstconnector housing 202 so that the connected portion 221 projects forwardfrom a front end surface 203 of the first connector housing 202 and ismovable in a front-back direction. Concretely, the large diameterportion 228 of the first ferrule 220 is slidably supported by theshoulder portion 230. The shoulder portion 230 defines a limit ofmovement in frontward. The front end of the first ferrule 220 isbevel-processed (chamfer-processed) and a bevel portion 223 is formed. Adiameter R₁ of the end surface 225 of the first ferrule 220 is smallerthan an outer diameter R₂ of the connected portion 221. A thickness ofthe tubular portion 212 is substantially equal to a thickness of thefirst outer jacket 140 of the first electro-optical composite cable 100.

In the present embodiment, the electro-optical composite cable 100 isalso inserted into the first bias member 206 composed of a coil springwhen the first electro-optical composite cable 100 is connected with thefirst ferrule 220 as described above. In this state, these componentsare inserted into through the back and into the first connecter housing202. After that, the first cable stopper 207 is fitted into the back ofthe first connector housing 202 so that the first bias member (coilspring) 206 is compressed and accommodated between a pushed surface 227of the first ferrule 220 and the first cable stopper 207. Thus, thefirst bias member 206 always forwardly biases the pushed surface 227 ofthe first ferrule 220. In other words, the first bias member 206 alwaysbiases the first ferrule 220 of the first connector 200 toward thesecond ferrule 220′ of the second connector 200′ (mentioned later) asillustrated in FIG. 14. In the present embodiment, the first bias member206 or the first cable stopper 207 does not contribute to the electricalconnection between the first metal conductor 130 and the first ferrule220. For this reason, the first cable stopper may be made of insulativematerial as mentioned above and the first bias member may be made of aninsulation member such as resin at a low cost.

As illustrated in FIG. 1 to FIG. 3, the second connector 200′ comprisesa second connector housing 202′ made of insulative material, a secondferrule 220′, a second sleeve (a second crimped portion) 240′, a secondbias member 206′, and a second cable stopper 207′ made of insulativematerial. Each component of the second connector 200′ has the structuresame as the respective component of the first connector 200. Forexample, similarly to the first connector housing 202, the secondconnector housing 202′ has a lock portion 204′ (mentioned later) and alock release member 205′ for operating the lock portion 204′ asillustrated in FIG. 1. As illustrated in FIG. 3, the second ferrule 220′is provided with a second tubular portion 212′. The tubular portion 212′functions as a second adjuster portion which adjusts a size differencebetween the second metal conductor 130′ and the second outer jacket 140′within the second sleeve 240′ which functions as the second crimpedportion.

As illustrated in FIG. 14, the adaptor 500 comprises an adaptor housing510 made of insulative material, a connection member 520 made ofconductive material, and an accommodation portion 550 composed of afirst part 530 and second part 540 holding the connection member 520. Asillustrated in FIG. 1, the adaptor housing 510 is formed with an lockhole 512 in which the lock portion 204 of the first connector 200 is tobe locked and an lock hole 512′ in which the lock portion 204′ of thesecond connector 200′.

As illustrated in FIG. 3 and FIG. 14, the connection member 520 holdsthe first ferrule 220 and the second ferrule 220′ and makes theelectrical connection between the first ferrule 220 and the secondferrule 220′. The illustrated connection member 520 has a shape of aso-called split sleeve which is made by forming a slit on thecylindrical tube in parallel with an axis. In the present embodiment, inorder to ensure the electrical connection between the first ferrule 220and the second ferrule 220′, an inner diameter of the connection member520 in an unconnected state is smaller than the outer diameter R₂ (seeFIG. 15) of either the connected portion 221 of the first ferrule 220 ora connected portion (a portion similar to the connected portion 221 ofthe first ferrule 220) of the second ferrule 220′, wherein theunconnected state is a state where the first ferrule 220 and the secondferrule 220′ are not inserted (i.e. not connected) into the connectionmember 520. Thus, when the first ferrule 220 and the second ferrule 220′are inserted into the connection member 520, the inner diameter of theconnection member 250 is widened. As the counter action, the connectionmember 520 grips the connected portion 221 of the first ferrule 220 andthe connected portion of the second ferrule 220′ from outside. By usingnot a mere connection member but the connection member 520, theelectrical connection is positively made between the first ferrule 220and the second ferrule 220′. Upon connecting the first electro-opticalcomposite cable 100 and the second electro-optical composite cable 100′with the first ferrule 220 and the second ferrule 220′, the electricalconnection may be made between the first ferrule 220 and the secondferrule 220′ even when a good electrical connection is not ensuredbetween the front end portions of the first ferrule 220 and the secondferrule 220′ because the front end portions of the first ferrule 220 andthe second ferrule 220′ are polished. Furthermore, the inner diameter ofthe connection member 520 of the present invention is larger than thediameter R₁ (see FIG. 15) of the front end surfaces of the first ferrule220 and the second ferrule 220. Therefore, when the first ferrule 220and the second ferrule 220′ are inserted into the connection portion520, the bevel portion 223 of the first ferrule 220 and a bevel portion(a portion similar to the bevel portion 223 of the first ferrule 220) ofthe second ferrule 220′ widen the inner diameter of the connectionmember 520. Thus the first ferrule 220 and the second ferrule 220′ aresmoothly inserted into the connection member 520. In the presentembodiment, the connection member 520 is made of the conductivematerial. Instead, for example the resinous connection member having ametal-plated surface may be used. However, in consideration of strengthand other conditions, the connection member 520 itself is preferred tobe made of the conductive material as described in the presentembodiment.

As illustrated in FIG. 3 and FIG. 14, the accommodation portion 550 iscomposed of two parts which are the first part 530 and the second part540 and holds the connection member 520 so that the inner diameter ofthe connection portion 520 is variable. In detail, as illustrated inFIG. 14, the accommodation portion 550 has an accommodation portion 552accommodating the connection member 520, and a first insertion opening532 and a second insertion opening 542 communicating with anaccommodation space 554. The accommodation space 554 has a space largerthan the outer diameter of the connection member 520 in a state wherethe connected portion of the first ferrule 220 or the connected portion221 of the second ferrule 220′ is inserted into the connection member520. The inner diameter of the connection member 520 is variable whenthe connected portion 221 of the first ferrule 220 or the connectedportion of the second ferrule 220′ is connected with the connectionmember 520. The first insertion opening 532 and the second insertionopening 542 are inserted with the connected portion 221 of the firstferrule 220 and the connected portion of the second ferrule 220′,respectively. The inner diameters of the first opening 532 and thesecond opening 542 are larger than the inner diameter of the connectionportion 520 in a normal state but smaller than the outer diameter of theconnection portion 520 in the normal state. Therefore, the connectionmember 520 will not fall away from the accommodation portion 550 afterthe accommodation portion 550 is made up by combining the first part 530and the second part 540. In the present embodiment, the accommodationportion 550 is made up by combining the first part 530 and the secondpart 540 so as to arrange the connection member 520 therein. Then theadaptor 500 is formed by holding and fixing the accommodation portion550 in the adaptor housing 510.

As described above, according to the optical connector of the presentembodiment, the conductive connection member 520 grips the first ferrule220 and the second ferrule 220′. Therefore, the electro-opticalconnection between the first ferrule 220 and the second ferrule 220′ isensured. In the present embodiment, explanation was made about a casethat the front end of the first ferrule 220 and the front end of thesecond ferrule 220′ are polished. However, needless to say, the presentinvention is appliable to a case that the good electrical connection ismade between the front end of the first ferrule 220 and the front end ofthe second ferrule 220′.

Furthermore, the first ferrule 220 and the second ferrule 220′ hasconductivity at least on the entire surface thereof. However, forexample, an end portion including a front end surface 225 a of a firstferrule 220 a may be partially made of insulative material asillustrated in FIG. 16 and FIG. 17 so that unintentional occurrence ofthe short-circuit at the front end of the first ferrule 220 a may beprevented (hereinafter, such ferrule is called a “composite type”).Similarly to the above-described first ferrule 220 (see FIG. 3), theillustrated first ferrule 220 comprises a connected portion 221 and alarge diameter portion 228 which has a substantially tubular shape andhas an outer diameter larger than the outer diameter of the connectedportion 221. The connected portion 221 of the present embodiment iscomposed of a front portion 222 made of insulative material and a backportion 224 made of conductive material and integrally formed with thelarge diameter portion 228.

As is clearly shown in FIG. 16, the front portion 222 is provided with ahole 229 in a center for holding the optical fiber and also with a partat a back which has an outer diameter similar than that of the frontpart. The outer diameter of the front portion 222 is almost equal to anouter diameter of a back portion 224. The back portion 224 is formed ofa base member made of copper and plated with nickel and gold. The backportion 224 and the large diameter portion 228 are electricallyconnected with the first metal conductor 130 of the firstelectro-optical composite cable 100. The first ferrule 220 a of thepresent embodiment is connected with the first electro-optical compositecable 100 by the above-described second wiring structure (FIGS. 8 to10). However, the use of the wiring structure is not limited thereto.The back portion 224 of the first ferrule 220 a may be made of othermaterial. However, at least the surface thereof is required to haveconductivity in order to make the electrical connection with the firstmetal conductor 130. For example, the first ferrule 220 a may be formedby preparing the base member made of resin and plating the surface withmetal. In this case, the back portion 224 and the large diameter portion228 are integrally formed with each other by resin. The respectivesurfaces are plated with metal. However, the base member of the firstferrule 220 a is preferred to be made of copper (metal) because thepresent embodiment employs the crimping process for the connection withthe first electro-optical composite cable 100.

The first ferrule 220 a of the present embodiment is formed by combininga member (a front member) including the front portion 222 with a member(a back member) including the back portion 224 and the large diameterportion 228. In detail, as illustrated in FIG. 16, the back member has acavity positioned inside the back member and is inserted with the frontmember. The first ferrule 220 a is formed by inserting the front memberinto the cavity.

When the first ferrule 220 a is used, as a matter of course, theabove-described adaptor 500 (see FIG. 3 and FIG. 14) is applicable tothe optical connector apparatus. However, an adaptor 500 a illustrated,for example, in FIG. 18 is more preferred to be applied. Similarly tothe above-described adaptor 500, the adaptor 500 a comprises an adaptorhousing 510 a made of insulative material and a connection member 520 bmade of conductive material and held by the adaptor housing 510 a (theconnection 520 b will be mentioned later). As illustrated in FIG. 19, inan optical connector apparatus 10 a of the present embodiment, the firstconnector 200 and the second connector 200′ comprise ferrules same asthe above-described ferrule 220 a (see FIG. 16 and FIG. 17).

As illustrated in FIG. 18 and FIG. 19, the adaptor housing 510 acomprises a projection 505 and an accommodation portion 550 a having asubstantially tubular shape and accommodating the connection member 520a. The accommodation portion 550 a of the present embodiment is notformed with the first part 530 and the second part 540, like theabove-described adaptor housing 510 (see FIG. 14), but is formedseamlessly and integrally with each other. The projection 505 preventsfingers or the like from being accidentally inserted in the adaptorhousing 510 a. A length of the projection 505 from an inner surface islonger than a length of the accommodation portion 550 a.

The connection member 520 a illustrated in FIG. 20 is accommodated inthe accommodation portion 550 a. The connection member 520 a comprisesreceiving portions 527 provided on both ends in a longitudinaldirection, a press-fit portions 551, and two spring portions 528 formedby making three cuts 526 along the longitudinal direction into an edgeportion 541 of each receiving portion 527. Each receiving portion 527receives the connected portion 221 of the first ferrule 220 a (or theconnected portion 221 of the second ferrule 220C along a predetermineddirection (insertion and ejection direction). The connection member 520a is provided with the spring portions 528 having relatively low springconstant so that the connection member 520 a is given a slight grippingforce. With this structure, when the first ferrule 110 a is insertedinto the connection member 520 a, the connection member 520 a isflexibly deformed so that the diameter thereof increases. Therefore, itmay be possible to deal with the first ferrule 220 a or the connectionmember 520 a which are different in size. Furthermore, the back portion224 of the first ferrule 220 a inserted into the connection member 520 ais electrically connected with the connection member 520 a through threeportions, i.e. two spring portions 528 and the receiving portion 527 ofthe connection member 520 a so that a connection reliability isimproved.

In the present embodiment, as illustrated in FIG. 18 to FIG. 20, theconnection member 520 a is press-fitted into the accommodation portion550 a of the adaptor housing 510 a so that the press-fit portions 551are locked to an inner wall of the accommodation portion 550 a. Thus,the connection member 520 a is accommodated in the accommodation portion550 a. After that, as illustrated in FIG. 24, the first connector 200 aand the second connector 200 a′ are connected with the adaptor 500 a.

Similarly to the above-described connection member 520, the connectionmember 520 a may be held by the adaptor 500 (see FIG. 14). In this case,the connection member 520 a is press-fitted into the first part 530 andthe second part 540 of the adaptor 500 so that the press-fit portions551 are locked an inner wall of the first part 530 and the second part540. Thus, the connection member 520 a is held.

As the connection member, a connection member having a slit, aconnection member having T-like wide recess in addition to the slit, ora connection member having an H-shaped cut (recess) 526 as illustratedin FIG. 21 may be used, wherein the H-shaped cut is perpendicular to aslit 523 defining a width of split of the connection member 520 b. Theconnection member may have a holding function as a sub function and anelectrical-connection function between the ferrules as a main functionwhile axis alignment of the ferrules may be carried out by using othermember which is specially provided.

An optical connector apparatus 10 b illustrated in FIG. 22 to FIG. 30 isan example of the optical connector using other types of the connectionmember. In the illustrated optical connector apparatus 10 b, componentsexcept for the first ferrule 220 a and the connection member 520 c arethe same as those of the above-described optical connector 10 (see FIG.1). The same reference numerals are given to the same components andtherefore the description thereof will be omitted.

As illustrated in FIG. 22 to FIG. 24, the optical connector apparatus 10b comprises a first connector 200 connected with a first electro-opticalcomposite cable 100, a second connector 200′ connected with a secondelectro-optical composite cable 100′, and an adaptor 500 relaying aconnection between the first connector 200 and the second connector200′.

As illustrated in FIG. 24, similarly to the above-described firstferrule 220 a (see FIG. 16 and FIG. 17), the first ferrule 220 b is ofthe composite type and has a structure similar to the first ferrule 220a. Specifically, the first ferrule 220 b comprises a connected portion221 composed of a front portion 222 made of conductive material and aback portion 224 made of insulative material, a large diameter portion228, a shoulder portion 230, and a first tubular portion 212. A wiringstructure of the first ferrule 220 b is different from that of the firstferrule 220 a. The first ferrule 220 b has the first wiring structure asillustrated in FIG. 4 and FIG. 5.

The first ferrule 220 b is held by the first connector housing 202 sothat a front portion 222 of the connected portion 221 projects forwardfrom a front end surface of the first connector housing 202 and ismovable in a front-back direction. The large diameter portion 228 isslidably supported by the shoulder portion 230. The shoulder portion 230defines a limit of movement in frontward. The first ferrule 220 binserted from a back of the first connector housing 202 is always biasedforwardly by the first bias member 206. The first bias member 206 may beformed with a low-cost insulating material such as resin or the like.

As illustrated in FIG. 24, similarly to the first ferrule 220 b, thesecond ferrule 220 b′ comprises a connected portion 221′ composed of afront portion 222′ and a back portion 224′, a large diameter portion228, a shoulder portion 230′, and a second tubular portion 212′.

The adaptor 500 has a structure substantially the same as the adaptor500 explained in the above-described embodiment (see FIG. 1 to FIG. 3)except that a connection member 520 c (a sleeve) is different.Specifically, as illustrated in FIG. 24, the adaptor 500 comprises theadaptor housing 510 made of insulative material, the connection member520 c made of conductive material, and the accommodation portion 550holding the connection member 520 c.

As is understood from FIG. 27 and FIG. 30, similarly to the adaptor 500(see FIG. 14) explained in the first embodiment, the accommodationportion 550 of the present embodiment is composed of two parts which area first part 530 and a second part 540. The accommodation portion 550has the accommodation space 554 accommodating the connection portion,and the insertion openings 532, 542 communicating with the accommodationspace 554. As described above, each inner diameter of the insertionopenings 532, 542 is smaller than an inner diameter (a diameter of aninner wall portion) of the accommodation space 554. In detail, theaccommodation space 554 is formed so as to accommodate the connectionmember 520 c while the insertion openings 532, 542 are formed so as toprevent the connection member 520 c from falling away from theaccommodation space 554.

As illustrated in FIG. 22, FIG. 23 and FIG. 27, in the presentembodiment, the accommodation portion 550 is made up by combining thefirst part 530 and the second part 540 so as to arrange the connectionmember 520 c therein. Then the adaptor 500 is formed by holding andfixing the accommodation portion 550 in the adaptor housing 510.

As illustrated in FIG. 24, FIG. 28 and FIG. 29, the connection member520 c of the present embodiment holds the first ferrule 220 b and thesecond ferrule 220 b′ and electrically connects the first ferrule 220 bwith the second ferrule 220 b′. When the first ferrule 220 b and thesecond ferrule 220 b′ are inserted into the connection member 520 c, theconnection member 520 c grips the front portion 222 formed on theconnected portion 221 of the first ferrule 220 b and the front portion222′ formed on the connected portion 221′ of the second ferrule 220 b′from outside so that they are electrically connected.

Referring to a structural feature of the connection member 520 c, asillustrated in FIG. 28 and FIG. 29, the connection member 520 c isformed by stamping a metal plate having two edge portions so that theedge portions are opposite to each other and thus forming a main bodyportion 522 having a tubular shape. In the present embodiment, anopposed-edges portion (joint portion) 524 is formed of the edgesportions opposite to each other is substantially formed of the edgeportions facing each other. Thus, the main body portion 522 is tubularas mentioned above. However, the present invention is not limited tothis structure. For example, the opposed-edges portion 524 may be formedby arranging the edges opposite to each other with a slight spacetherebetween. In this case, the main body portion 522 may have a shapethat is substantially tubular. In the present embodiment, the entireconnection member 520 c may be regard as the main body portion 522because it is processed by stamping the metal plate having a simpleshape. Even if a frond end and a back end are provided withcharacteristic shape, a part of the connection member 520 c is requiredto be provided with a portion corresponding to the main body portion 522in order to keep a suitable ferrule-holding function.

The main body portion 522 comprises three ferrule contact portions 525a, 525 b, 525 c which are brought into contact with the first ferrule220 b and the second ferrule 220 b′ when the connection member 520 cholds the first ferrule 220 b and the second ferrule 220 b′. Theferrule-contact portions are separated from each other in a plane (aperpendicular plane) perpendicular to the axis-direction. Concretely,the ferrule contact portion 525 a is positioned at an opposite side ofthe opposed-edges portion 524 in the perpendicular plane. The ferrulecontact portions 525 b, 525 c are arranged so that each of the ferrulecontact portions 525 b, 525 c, the ferrule contact portion 525 a and acenter of the connection member 520 c forms a central angle of 120degrees. In other words, the illustrated ferrule contact portions 525 a,525 b, 525 c are arranged on the main body portion at about 120 degreeintervals in the perpendicular plane. Each of the ferrule contactportions 525 a, 525 b, and 525 c has a linear shape in the perpendicularplane and extends along the axis-direction of the connection member 520c. In other words, each of the ferrule contact portions 525 a, 525 b and525 c has a long and thin plate-like shape. As a result, as illustratedin FIG. 29, the connection member 520 c has a shape like a triangularrice ball (a shape of a triangle having rounded corners) in theperpendicular plane.

In the case of the connection member 520 c, having the above-describedshape, a difference between an inscribed circle and a circumscribedcircle shown in FIG. 29 may be made larger than the thickness of theconnection member 520 c. In other words, the suitable ferrule-holdingfunction can be obtained by adjusting the inscribed circle while theconnection member 520 c is prevented from rattling in the accommodationspace 554 of the accommodation portion 550 by adjusting thecircumscribed circle. Moreover, in the case of the connection member 520c of the present embodiment, the adjustment may be carried out duringthe stamp process of the metal plate or by the stamping process which iscarried out afterwards. Therefore, according to the present embodiment,the circumscribed circle and the inscribed circle of the connectionmember 520 c are easily adjusted by low-cost stamping so that both thesuitable holding of the ferrule and the prevention of the rattling inthe accommodation portion 550 can be achieved.

As a further modification of the connection member, the connectionmember may be constituted to have more suitable structure for theconnection with the electro-optical composite cable, for example, suchas a connection member 520 d illustrated in FIG. 31 to FIG. 33. Indetail, the connection member 520 d is formed by stamping a metal platehaving two edge portions so that the edge portions are opposite to eachother and thus forming a main body portion 522 d having a tubular shape.An opposed-edges portion formed of the edge portions opposite to eachother is substantially formed of the edge portions facing each other.The main body portion 522 d of the connection member 520 d is providedwith ferrule contact portions 525 a, 525 b, 525 c by stamping in a likemanner of the above-described ferrule 520 c (see FIG. 29). The ferrulecontact portion 525 a is positioned at an opposite side of theopposed-edges portion 524 in the perpendicular plane. The ferrulecontact portions 525 b, 525 c are arranged so that each of the ferrulecontact portions 525 b, 525 c, the ferrule contact portion 525 a and acenter of the connection member 520 c forms a central angle of 120degrees. In other words, the illustrated ferrule contact portions 525 a,525 b, 525 c are arranged on the main body portion at about 120 degreeintervals in the perpendicular plane.

The connection member 520 d is not obtained by stamping the metal platehaving a simple structure but is obtained by punching out a front endand a back end so as to have a predetermined shape and followed bybending. As a result, each of the front end and the back end has a pairof spring portions 528 d and a support portion 529. The spring portions528 d is provided to correspond to two ferrule contact portions 525 b,525 c positioned apart from each other by the same distance from theopposed-edges portion 524 which locates between the ferrule contactportion 525 b and the ferrule contact portion 525 c. The spring portions528 d are brought into contact with the back portion 224 provided on theconnected portion 221 of the first ferrule 220 b illustrated in FIG. 24(or the back portion 224′ provided on the connected portion 221′ of thefirst ferrule 220 b′). The spring portions 528 d in an normal stateproject inwardly than the inscribed circle defined by the main bodyportion 522 d (see FIG. 33) in order to secure more solid electricalconnection with the first ferrule 220 b (or the second ferrule 220 b′).On the other hand, the support portion 529 is provided to correspond tothe opposed-edges portion 524. Specifically, the support portion 529 ispositioned midway between the pair of spring portions 528 d in theperpendicular plane. As illustrated in FIG. 31, the support portion 529is provided so as to minimize a clearance between an inner wall of theaccommodation space 554 of the accommodation portion 550 and an outercircumference of the connection member 520 d. The connection member 520d is accommodated in the accommodation space 554 of the connectionmember 550 with clearance. Since the two spring portions 528 d arepositioned a part from a line extending in the center of the connectionmember 520 d, in case if the support portion 529 is not provided, thereis a possibility that the first ferrule 220 b (or the second ferrule 220b′) may be misaligned in the accommodation space 554 in an upward and adownward direction. In this case, when the first ferrule 220 b (thesecond ferrule 220 b′) is to be inserted into the connection member 520d, the first ferrule 220 b (the second ferrule 220 b′) will be broughtinto contact with an edge of the connection member 520 d so that theinsertion may be failed or may not be well guided. However, in casewhere the support portion 529 is provided, the clearance between theaccommodation space 554 of the accommodation portion 550 and an outercircumference of the connection member 520 d, i.e. the clearance, isminimized so that the misalignment in the upward and downward directionsis resolved. Thus, when inserted into the connection member 520 d, thefirst ferrule 220 b (the second ferrule 220 b′) is guided toward theconnection member 520 d and inserted securely.

The support portion 529 may or may not have elasticity. The supportportion 529 may be initially brought into contact with the inner wall ofthe accommodation portion 550 or may be brought into contact after thefirst ferrule 220 b (or the second ferrule 220 b′) is inserted into theconnection member 520 d.

In the above-explained first embodiment, the explanation was made aboutthe first to the fourth wiring structures (see FIG. 4, FIG. 5 and FIG. 8to FIG. 13) as four types of the wiring structure, the adaptor housing510 (see FIG. 14, or FIG. 27) and the adaptor housing 510 a (see FIG.19) as two types of the adaptor housing, the connection member 520 (seeFIG. 2), the connection member 520 a (see FIG. 20), the connectionmember 520 b (see FIG. 21), the connection member 520 c (see FIG. 28)and the connection member 520 d (see FIG. 32) as five types of theconnection members, and further the metal type ferrule 220 (see FIG. 3)and the composite type ferrules 220 a and 220 b (see FIG. 16 and FIG.24) as two types of the ferrules. However, the optical connectorapparatus of the present embodiment is not limited thereto. The opticalconnector apparatus may be constituted by selecting the most suitablecomponents and combining them.

The optical connector apparatus according to the above-describedembodiment comprises three components including two connectors (thefirst connector 200 and the second connector 200′) and the adaptor.However, the present invention is not limited thereto. The concept ofthe present invention can be applied to any kind of the opticalconnector apparatus having the connection member which holds twoferrules in a state that the ferrules are butted (faced) with eachother.

Second Embodiment

The optical connector apparatus according to the above-described firstembodiment connects the electro-optical composite connector with anotherelectro-optical composite connector through the adaptor. However, anoptical element such as a photo diode may be used as an object which isconnected through the adaptor.

As illustrated in FIG. 34, an optical connector apparatus according to asecond embodiment comprises the ferrule 220 connected with theelectro-optical composite cable 100, an optical element 800 such as thephoto diode, and a housing 810 holding the optical element 800. Theelectro-optical composite cable 100 has the structure similar to that ofthe electro-optical composite cable of the first embodiment. Themetal-type ferrule 220 (see FIG. 3) according to the first embodiment isused. Therefore, the ferrule 220 of the present embodiment comprises theconnected portion 221, the large diameter portion 228, the shoulderportion 230 and the tubular portion (not shown) which functions as theadjuster portion. A sleeve 240 which functions as the crimped portion iscrimped in a state that the size difference is adjusted by the tubularportion so that the electro-optical composite cable100 is connected withthe ferrule 220. The optical connector apparatus is also provided withthe bias member (a coil spring) 206 which is arranged so as to alwayspush a pushed portion 227 of the ferrule 220 and biases the ferrule 220toward the optical element 800. Similarly to the first embodiment, theferrule 220, the sleeve 140 and the bias member 206 may be accommodatedin a space defined by a cable stopper and an-insulative connectorhousing (see FIG. 3).

The optical element 800 is installed on the substrate (not shown) andcomprises terminals 801 connected with conductive patterns (not shown)on the substrate. The housing 810 of the present embodiment is made ofconductive material and comprises an installation surface 802 to beinstalled on the substrate. The housing 810 is formed with a tubularconnection portion 820 extending toward the ferrule 220. The connectedportion 221 of the ferrule 220 is inserted into the connection portion820 so that a contact end surface 812 of the connection portion 820 isbrought into contact with a contact surface 233 which faces forward anddefines a boundary between the connected portion 221 of the ferrule 220and the large diameter portion 228. As a result, an electricalconnection between the ferrule 220 and the housing 810 is established.In addition, a distance between the optical element 800 and a front endsurface 225 of the ferrule 220 is fixed because the contact surface 233of the ferrule 220 is brought into contact with the contact-end surface812. Therefore, an optical connection between the optical element 800and the optical fiber held by the ferrule 200 may be stable.

In the present embodiment, the housing 810 is entirely made ofconductive material. However, for example, a part of the housing may bemetal-plated so that the housing is partially conductive and that anelectrical path may be established between the ferrule 220 and thesubstrate.

Third Embodiment

In the optical connector apparatus according to the above-describedsecond embodiment, the optical element is held by the housing. However,the optical element may be held by an adaptor 900 illustrated in FIG.35. Hereinbelow, an explanation will be made about a third embodiment ofthe optical connector apparatus which comprises the connector and theadaptor holding the optical element and relaying a connection betweenthe connector and the optical element. As the connector to be connectedwith the adaptor 900, the above-described first connector 200 (seeFIG. 1) according to the first embodiment may be used. In this case, theferrule 220 (see FIG. 14), the ferrule 220 a (see FIG. 16) or theferrule 220 b (see FIG. 24) may be used as the ferrule to be held by thefirst connector 200. Hereinbelow, detailed descriptions of the connectorand the ferrule will be omitted. An explanation will be made only aboutthe adaptor and the connection member held by the adaptor.

As illustrated in FIG. 35 to FIG. 37, the adaptor 900 of the presentembodiment comprises a housing 910 having an insulation property, and aconnection member 930 made of the conductive material held by thehousing 910.

As illustrated in FIG. 35 to FIG. 37, the housing 910 has a tubularaccommodation portion 950 which accommodates the connection member 930,and an element-accommodation portion 960 which accommodates the opticalelement (not shown). The optical element is accommodated in theelement-accommodation portion 960 so as to face an end surface of theoptical fiber held by the ferrule of the connector when the connector isconnected with the adaptor 900.

As illustrated in FIG. 36, the connection member 930 comprises astructure as if the connection member 520 a illustrated in FIG. 20 intohalves. Specifically, the connection member 930 is formed by attachingan extended-connection portion 970 to a tubular shaped portion whereinthe extended-connection portion 970 extends in a diameter direction ofthe tubular shaped portion. In detail, the connection member 930comprises a receiving portion 927 receiving the ferrule of the connectoralong a predetermined direction, two spring portions formed by makingthree cuts 926 along the longitudinal direction in an end portion 941 ofthe receiving portion 927, and the above-described extended-connectionportion 970. As is clear from FIG. 36, the extended-connection portion970 is provided on an end portion opposite to the end portion 941 whichis formed with the above-described cuts 926. The extended-connectionportion 970 is electrically connected with a circuit pattern on thesubstrate when the adaptor of FIG. 35 is installed on the substrate (notshown). Similarly to the connection member 520 a illustrated in FIG. 20,the connection member 930 is formed with the spring portions 928 whichhas a relatively low elastic constant so that a small amount of grippingforce is given to the connection member 930. With this structure, forexample, when the connection member 930 is inserted with theabove-described ferrule 220 (see FIG. 1 to FIG. 3), the connectionmember 930 is elastically deformed so that the diameter thereofincreases. Thus, the connection member 930 is suitable for variety sizesof the ferrules 220 or the connection members 930. Even when thecomposite-type ferrule 220 a (or the ferrule 220 b: see FIG. 24) isused, the back portion 224 (or the back portion 224′) of the ferrule 220a which is inserted into the connection member 930 is electricallyconnected with the three points which are two spring portions 928 andthe accommodation portion 927. Therefore, each of the ferrules canimprove the connection reliability with the connection member 930.

The connection member 930 is accommodated in the accommodation portion950 in the similar manner to the connection member 520 a (see FIG. 20)that the connection member 930 is press-fitted into the accommodationportion 950 so as to engage the press-fit portions 951 with an innerwall of the accommodation portion 950.

Fourth Embodiment

In the above-described embodiments, the explanations have been madeabout the connection established between the ferrule and the connectionmember wherein the connection member grips the ferrule. As illustratedin FIG. 38, an optical connector apparatus according to a fourthembodiment comprises the first connector 200 connected with the firstelectro-optical composite cable 100, the second connector 200′ connectedwith the second electro-optical composite cable 100′, and an adaptor 500a relaying a connection between the first connector 200 and the secondconnector 200′.

As illustrated in FIG. 38 to FIG. 41, components, except for aconnection member 520 e and a first ferrule 220 c, of the opticalconnector apparatus 10 c according to the present embodiment are similarto that of the optical connector apparatus 10 a (see FIG. 19). The samereference numerals are given to the components similar to theabove-described first structure and, therefore, the description of thosecomponents will be omitted.

As illustrated in FIG. 38 to FIG. 41, the first ferrule 220 c iscomposed of a connected portion 221 made only of insulative material andthe large diameter portion 228 made of conductive material (hereinafter,a ferrule of such type is called the “insulation type”). In detail, theconnected portion 221 is a tubular insulator formed with a hole 229 andis inserted in the large diameter portion 228 so as to form a front endof the ferrule 220 c. The hole 229 holds the optical fiber in itscenter. The large diameter portion 228 is formed so as to constitute atubular shaped frontend portion of a conductive member which iselectrically connected with the first metal conductor 130 of the firstelectro-optical composite cable. In addition, an edge of the largediameter portion 228, i.e. a boundary between the large diameter portion228 and the connected portion 221, forms a contact portion 233 having aring-shape.

As illustrated in FIG. 38 and FIG. 41, the adaptor 500 a according tothe present embodiment comprises an adaptor housing 510 a made ofinsulative material and a connection member 520 e wherein the connectionmember 520 e is made of conductive material and is held by the adaptorhousing 510 a.

As illustrated in FIG. 41, the adaptor housing 510 a comprises aprojection 505 and a tubular accommodation portion 550 a whichaccommodates the connection member 520 e. The projection 505 preventsfingers or the like from being accidentally inserted in the adaptorhousing 510 a. A length of the projection from an inner surface islonger than a length of the accommodation portion 550 a.

As illustrated in FIG. 42, the connection member 520 e is made ofconductor and has a substantially tubular shape. The connection member520 e comprises the receiving portion 527 receiving the end portion ofthe first ferrule 220 c (or the second ferrule 220 c′) in thepredetermined direction (the insertion and the ejection direction),support portions 552 extending in the predetermined direction, thespring portions 528 e extending from the support portions 552 in aperipheral direction of the connection member 520 e, conductive portions541 e provided on the front ends of the spring portions 528 e, andpress-fit portions 551. A free end portion of the each of the springportions 528 e has a cut portion which is formed by making a cut in anend portion, into which a first ferrule 220 c (or the second ferrule 220c′) is inserted, along the insertion direction. The conductive portion541 e of the present embodiment is supported by the spring portions 528e so as to be displaceable in the predetermined direction. An endportion 554 a of the support portion 552 and an end portion 554 b of thereceiving portion 527 are positioned at the same position in theinsertion and the ejection directions. The conductive portion 541 e ofthe present embodiment is positioned closer to the ferrule than the endportions 554 a, 554 b and is supported by the spring portions 528 e soas to be displaceable in the predetermined direction.

The connection member 520 e is accommodated in the accommodation portion550 a of the adaptor housing 510 a in a manner as follows. Theconnection member 520 e is press-fitted into the accommodation portion550 a. The press-fit portions 551 are engaged with an inner wall of theaccommodation portion 550 a. The conductive portion 541 e of theconnection member 520 e is projected from an end portion 502 a of theaccommodation portion 550 a.

In the electro-optical connector apparatus having the above-describedthese structure, the contact portion 233 of the first ferrule 220 c isbrought into contact with the conductive portion 541 e of the connectionmember 520 e when the first connector 200 is inserted into the adaptor500 a. In this state, when the first connector 200 is pushed toward theadaptor 500 a, the conductive portion 541 e slides on the contactsurface 233 and is displaced. The connected portion 221 is inserted intothe connection member 520 e till the contact surface 233 is brought intocontact with the end portions 554 a, 554 b of the connection member 520e so that a connection of the first ferrule 220 c and the connectionmember 520 e is completed. An electrical connection and an opticalconnection are established between the first connector 200 and thesecond connector 200′. The conductive portion 541 e of the connectionmember 520 e of the present embodiment is supported by the springportions 528 e. Therefore, the conductive portion 541 e is securelybrought into contact with the contact surface 233 by the restoring forceof the spring portion 528 e. In addition, the contact surface 233 isbrought into contact with the end portions 554 a, 554 b so thatreliability of an electrical connection between the adaptor 500 a andthe first connector 200 is increased. A portion including the endsurface of the first ferrule 220 c of the present embodiment has aninsulation property so that, similarly to the above-describedcomposite-type ferrule, unintentional occurrence of the short-circuit atthe front end of the first ferrule 220 c may be prevented.

As explained above, according to the present embodiment, the ferruleheld by the connector is brought into contact with the connection objectso that the electrical and the optical connections are established. Inthe above-described fourth embodiment, the component which constitutesthe above-described connection object may be regard as a singlecomponent with the second connector 200′ and the adaptor 500 a combinedtogether.

Fifth Embodiment

Applying a concept similar to the above fourth embodiment, theconnection object may be not only the combination of the connector andthe adaptor but also a housing which accommodates the optical elementsuch as the photo diode, for example. From this point of view, theexplanation of the optical connector apparatus according to a fifthembodiment of the present invention will be made about an opticalconnector apparatus which comprises the connection object having theoptical element. Similar to the fourth embodiment, the connector (seeFIG. 39 and FIG. 40) which comprises the insulation-type ferrule 220 cmay be used as a connector connected with the connection object. Forthis reason, a detailed explanation about the connector will be omitted.

With reference to FIG. 43 to FIG. 45, the connection object 900 acomprises a housing 910 a having insulation property, the connectionmember 930 a made of conductive material and held by the housing 910 aand the optical element (not shown).

As illustrated in FIG. 43 and FIG. 45, the housing 910 a has a tubularaccommodation portion 950 a accommodating the connection member 930 a,and an element accommodation portion 960 accommodating the opticalelement (not shown). The optical element is held by the housing 910 a sothat, when the ferrule is inserted into the connection member 900 a, theoptical element faces the end surface of the optical fiber which is heldby the ferrule.

As illustrated in FIG. 44, the connection member 930 a comprises astructure as if the connection member 520 e illustrated in FIG. 42 isdivided into halves. Specifically, the connection member 930 a is formedso that an extended-connection portion 970 extending in a diameterdirection is attached to a tubular shaped part of the connection member930 a. In detail, the connection member 930 a comprises receivingportions 927 a receiving the end portion of the first ferrule in thepredetermined direction, support portions 952 extending thepredetermined direction, spring portions 928 a extending from thesupport portions 952 in a peripheral direction of the connection member930 a, conductive portions 941 a provided on front ends of the springportions 928 a, and the above-described extended-connection portion 970.Similarly to connection member 520 e of the fourth embodiment, theconductive portion 941 a is formed so that an end portion 954 a of thesupport portion 952 and an end portion 954 b of the receiving portion927 a are positioned at the same position in the insertion and theejection directions. The conductive portion 941 a of the presentembodiment is projected toward the ferrule than the end portions 954 a,954 b and is supported by the spring portions 928 a so as to bedisplaceable in the predetermined direction. As is clear from FIG. 44,the extended-connection portion 970 is provided on an end portionlocated opposite to another end portion which is provided with theconductive portion 841 a. When the connection object 900 a is installedon the substrate (not shown), the extended-connection portion 970 iselectrically connected with a circuit pattern on the substrate.

The connection member 930 a is accommodated in the accommodation portion950 a similarly to the case of the adaptor 900 a (see FIG. 35) of theoptical connector apparatus according to third embodiment. Specifically,the connection member 930 a is press-fitted into the accommodationportion 950 a so that the press-fit portions 951 are engaged with aninner wall of the accommodation portion 950 a. The conductive portion941 a of the connection member 930 a is projected from an end portion ofthe accommodation portion 950 a. Thus, the connection member 930 a isaccommodated in the accommodation portion 950 a.

In the optical connector apparatus comprising the connection objecthaving the above-described structure, the contact surface 233 of thefirst ferrule 220 c is brought into contact with the conductive portion941 a when the first connector 200 as illustrated in FIG. 40 is insertedinto the connection object 900 a. In this state, when the ferrule 220 cis further pushed therein, the conductive portion 941 a slides on thecontact surface 233 and is displaced. The connected portion 221 isinserted till the contact surface 233 is brought into contact with theend portions 954 a, 954 b of the connection member 930 a so that aconnection between the first ferrule 220 c and the connection object 900a is completed. Thus, an electrical connection and an optical connectionare made between the connector and the connection object 900 a. Also inthe present embodiment, the conductive portion 941 a is securely broughtinto contact with the contact surface 233 by a restoring force of thespring portions 928 a. In addition, the contact surface 233 is broughtinto contact with the end portions 954 a, 954 b so that reliability ofan electrical connection between the connection object 900 a and theelectro-optical composite connector increases.

Sixth Embodiment

In the above-described optical connector apparatus, the connector holdsthe ferrules identical with each other. As a matter of course, when theconnector is connected with the connection member, two ferrules held byone connector are electrically connected with the connection member atthe same time. On the other hand, in the optical connector apparatus 10d of the present embodiment, when the connector is connected with theconnection member, a timing of the electrical connection with theconnection member is delayed within at least two or more ferrules. Indetail, as illustrated in FIG. 46 to FIG. 49, the opticalconnector-apparatus 10 d comprises a first connector 200 and a secondconnector 200′ connected with a first electro-optical composite cable100 and a second electro-optical composite cable 100′, respectively, andthe adaptor 500 relaying a connection between the first connector 200and the second connector 200′. In the present embodiment, the firstconnector 200, the second connector 200′ and the adaptor 500, and abelow described first ferrule 220, a first ferrule 220 b and aconnection member 520 d are the same as those explained above. The samereference numerals are given to those components and, therefore, thedescription of those components will be omitted. In the above-describedembodiment, the term “first ferrule” indicates two ferrules which areheld by the first connector while the term “second ferrule” indicatestwo ferrules which are held by the second connector. In the sixthembodiment, one connector (the first connector or the second connector)includes two ferrules, and the two ferrules are called “first ferrule”and “second ferrule”. In other words, the first ferrule and the secondferrule are held by a common connector.

As illustrated in FIG. 46 to FIG. 48, the first connector 200 comprisesa first connector housing 202 made of insulative material, the firstferrule 220, the second ferrule 220 b, a first sleeve (a first crimpedportion) 240, a first bias member 206, and a first cable stopper 207made of insulative material.

The first connector 200 comprises the metal-type ferrule 220 and thecomposite-type ferrule 220 b. As illustrated in FIG. 48, the firstferrule 220 has the connected portion 221, the large diameter portion228, the shoulder portion 230, and the tubular portion 212. As describedabove, the connected portion 221 and the large diameter portion 228 ofthe first ferrule 220 are made of the conductive material. The connectedportion 221 of the first ferrule 220 functions as a first conductiveportion. On the other hand, as illustrated in FIG. 49, the secondferrule 220 b has the connected portion 221, the large diameter portion228, the shoulder portion 230, and the tubular portion 212. Theconnected portion 221 of the second ferrule 220 b is composed of thefront portion 222 made of the insulative material and the back portion224 made of the conductive material and integrally formed with the largediameter portion 228. The back portion 224 functions as a secondconductive portion. In the present embodiment, as illustrated in FIG.46, the first ferrule 220 itself functions as the first conductiveportion. Therefore, a distance between a first front end surface 225 ofthe end surface of the first ferrule 220 and the first conductiveportion is zero. On the other hand, a second end surface 225 a of theend surface of the second ferrule 220 b is apart from the secondconductive portion (the back portion 224) by a length of the frontportion 222 which is made of an insulative material and which ispositioned between the second end surface 225 a and the secondconductive portion. In other words, a distance between the first endsurface 225 and the first conductive portion (the first ferrule 220 initself) is different from a distance between the second end surface 225a and the second conductive portion (the back portion 224).

As explained in the first embodiment, the first ferrule 220 is connectedwith the first electro-optical composite cable 100 by theabove-described wiring structure (see FIG. 4 and FIG. 5). In the presentembodiment, the first ferrule 220 always pushes the first ferrule 220and the second ferrule 220 b forward by the first bias member 206. Thefirst bias member 206 may be made of the insulative material such asresin.

The second connector 200′ has a mirror-image structure of the firstconnector. The second connector 200′ has a structure same as the firstconnector 200 except for an arrangement of the second ferrule 220′ andthe second ferrule 220 b′ which are in reversed positions of those inthe first connector 200. As illustrated in FIG. 46 to FIG. 49, thesecond connector 200′ comprises a second connector housing 202′ made ofthe insulative material, a first ferrule 220′, a second ferrule 220 b′,a second sleeve (a second crimped portion) 240′, a second bias member206′, and a cable stopper 207′ made of the insulative material.

Similarly to the first ferrule 220 and the second ferrule 220 b, of thefirst connector 200, the first ferrule 220′ of the second connector 200′is the composite-type ferrule (see FIG. 24) while the second ferrule 220b′ is the metal-type ferrule (see FIG. 3). A distance between a frontend surface of the first ferrule 220′ and a first conductive portion (aback portion 224′) is different from a distance between a front endsurface of the second ferrule 220 b′ and a second conductive portion(the second ferrule 220 b′ in itself).

As illustrated in FIG. 46 to FIG. 49 and FIG. 50 to FIG. 53, the adaptor500 of the present embodiment comprises an adaptor housing 510 made ofthe insulative material, two connection member 520 d made of theconductive material (see FIG. 32), and an accommodation portion 550accommodating the connection member 520 d. As illustrated in FIG. 46,the adaptor housing 510 is formed with an lock hole 512 locked with thelock portion 204 of the first connector 200, an lock hole 512′ lockedwith the lock portion 204′ of the second connector 200′, and theaccommodation portion 550.

As understood from FIG. 47 and FIG. 53, the accommodation portion 550 iscomposed of two parts which are a first part 530 and a second part 540.Furthermore, the accommodation portion 550 has an accommodation space554 in which the connection member 520 d is positioned, a firstinsertion opening 532 and a second insertion opening 542 wherein thefirst insertion opening 532 and a second insertion opening 542communicate with the accommodation space 554. Each of inner diameters ofthe first insertion opening 532 and the second insertion opening 542 issmaller than an inner diameter of the accommodation space 554 (adiameter of the inner walls). Therefore, the accommodation space 554 isable to accommodate the connection member 520 d while the firstinsertion opening 532 and the second insertion opening 542 are made sothat the connection member 520 d will not fall out from theaccommodation space 554.

As illustrated in FIG. 48, one of the connection members 520 d grips theconnected portion 221 (a first end portion) of the first ferrule 220 ofthe first connector 200 and the connected portion 221′ (the first endportion) of the first ferrule 220′ of the second connector 200′ so as toelectrically connect between them. On the other hand, as illustrated inFIG. 49, the other one of the connection member 520 d grips theconnected portion 221 (a second end portion) of the second ferrule 220 bof the first connector 200 and the connected portion 221′ (the secondend portion) of the second ferrule 220 b′ of the second connector 200′so as to electrically connects between them.

As described above, in the optical connector apparatus of the presentembodiment, each of the first ferrule 220 and the second ferrule 220 bhas a length between the end surface and the conductive portion, and thelengths are different from each other. Therefore, when the firstconnector 200 or the second connector 200′ is connected with the adaptor500, their conductive portions are connected with the connection member520 d of the adaptor 500 with a time lag. Thus, the hot swapping can becarried out.

The members of the optical connector apparatus according to the presentinvention are not limited to the above-mentioned members. For example,the already-explained first to the fourth wiring structure (see FIG. 4,FIG. 5, FIG. 8 to FIG. 13) may be used as the wiring structure betweenthe ferrule and the optical composite cable, the adaptor housing 510(see FIG. 14 or FIG. 27) or 510 a (see FIG. 19) may be used as theadaptor housing, the connection member 520 (see FIG. 2), 520 a (see FIG.20), 520 b (see FIG. 21), 520 c (see FIG. 28), or 520 d (see FIG. 32)may be used as the connection member, and the above components may be inan appropriate combination. Furthermore, one connection member of thetwo connection members comprised by the adaptor may be used as theconnection member 520 e (see FIG. 42) connected with the connectionmember by contacting the ferrules. In this case, an adaptor similar tothe adaptor 500 a illustrated in FIG. 19 may be used for the connectionmember 520 e and the insulation-type ferrule 220 c (see FIG. 39 and FIG.40) may be used for the ferrule brought into contact with the connectionmember. Moreover, for example, the first ferrules may be connectedthrough the connection member while the second ferrules may be connectedby contacting their end surfaces with each other. With these structures,when the connector is connected with the adaptor, timings of theelectrical connections through the plurality routes may be differentfrom each other.

Seventh Embodiment

The optical connector apparatus comprises two connectors and the adaptorrelaying them. However, the optical connector may have the connector andthe adaptor comprising the optical element.

As for an example of such optical connector wherein the connectionmember is connected with the ferrule by gripping, the adaptor 900 andthe connection member 930 illustrated in FIG. 35 to FIG. 37 may be used.As the ferrule which is connected with the connection member 930, themetal-type ferrule 220 (see FIG. 3) or the composite-type ferrule 220 a(see FIG. 16 and FIG. 7: the composite-type ferrule illustrated in FIG.24 may be appliable) may be used. In this case, similarly to thestructures of the first ferrule and the second ferrule of the opticalconnector apparatus 10 d explained with reference to FIG. 46, forexample, the metal-type ferrule 220 may be used for the first ferrulewhile the composite-type ferrule 220 b (or the ferrule 220 a) may beused for the second ferrule. Applying this structure, similar to thesixth embodiment, the distances between the first end surface 225 of thefirst ferrule 220 and the connected portion 221 (the first conductor) isdifferent from the distance between the second end surface 225 a of thesecond ferrule 220 b and the back portion 224 (the second conductor).Therefore, a timing of the electrical connection between the firstferrule 220 and one of the connection member 930 is different from atiming of the electrical connection between the second ferrule 220 a andthe other one of the connection members 930. As a result, the hotswapping may be possible.

Either the first ferrule or the second ferrule may be applied to theconnection method which establishes the connection between theconnection member and the ferrule brought into contact with theconnection member. In this method, for example, the adaptor 900 aillustrated in FIG. 43 to FIG. 45 may be used for the adaptor and acombination of the connection member 930 and the connection member 930 amay be used for the connection members. The metal-type ferrule 220 orthe composite-type ferrule 220 a (or the ferrule 220 b) may be used forthe ferrule connected with the connection member 930. Theinsulation-type ferrule 220 c (FIG. 39 and FIG. 40) may be used for theferrule connected with the connection member 930 a. Applying thisstructure, a distance between the first front end surface 225 of thefirst ferrule 220 (or 225 a) and the first conductive portion (adistance being zero in case of the metal-type ferrule/a distancecorresponds to a length of the front portion 222 in case of thecomposite type ferrule) is different from a distance between the secondfront end surface 225 c of the second ferrule 220 c and the secondconductive portion (a distance corresponding to a length of theconnected portion 221). Therefore, a timing of the electrical connectionbetween one of the ferrules (the metal-type or the composite-type) andthe connection member 930 is different from a timing of the electricalconnection between the other one of the ferrules (the insulation-type)and the connection member 930 a. As a result, the hot swapping may bepossible.

Furthermore, the explanation was made about the connector having twoferrules which are the first ferrule and the second ferrule in theabove-described embodiment. However, the present invention is notlimited thereto. For example, three or more ferrules may be installed tothe connector. In this case, each of the ferrules may have a distancebetween the end surface and the conductive portion, and each of thedistances may be different in length from each other. For example, thefirst connector 200 may have the first ferrule 220 of the metal-type,the second ferrule 220 a (or the ferrule 220 b) of the composite-typeand a third ferrule of the composite-type. On the other hand, each ofthe first to the third ferrules of the first connector 200 may be formedwith the composite-type ferrule. In such case, a distance between athird conductive portion (a back part of the connected portion) which isformed on the third ferrule as the conductive portion and a third endsurface which is an end surface of the third ferrule may be differentfrom either a distance between the first front end surface 225 and thefirst conductive portion (the first ferrule 220 in itself) or a distancebetween the second front end surface 225 a and the second conductiveportion (a back portion 224). The combination of the first ferrule, thesecond ferrule and the third ferrule may be made up by selecting theappropriate one from the metal-type ferrule 220, the composite-typeferrule 220 a (or the ferrule 220 b) or the insulation-type ferrule 220c. Needless to say, any of the first to the fourth wiring structures(see FIG. 4, FIG. 5 and FIG. 8 to FIG. 13) may be applied to eachferrule.

Eighth Embodiment

Finally, an explanation will be made about variation examples of thefront end surfaces of the ferrules used for the above-describedembodiment. In a case where the front end of the ferrule is not polishedin order to make the electrical connection between the front ends of theferrules, the front end of the ferrule may be formed as illustrated, forexample, in FIG. 54 and FIG. 55. A recess portion 226 e is formed acrossa center of the front end surface 225 e of a ferrule 2200 e asillustrated in FIG. 54. The recess portion 226 e has a rectangular shapewhen the ferrule 2200 e is seen from the front end.

A recess portion 226 f is formed on the front end surface 226 f of aferrule 2200 f illustrated in FIG. 55. The recess portion 226 f has afan-like shape which has a central angle of 180 degree or less when theferrule 2200 f seen from the front. In the case of the ferrule 2200 eand the ferrule 2200 f illustrated in FIG. 54 and FIG. 55, respectively,the optical fiber may be scratched and stressed within the recessportion 226 e and 226 f of the ferrule 2200 e and 2200 f, respectively,when the optical fiber is stressed and cut so that the front end surfaceof the optical fiber is positioned at the position (i.e. inner space ofthe recess portion 226 d and 226 e) lower than the front end surface 225e and 225 f of the ferrule 2200 e and the ferrule 2200 f, respectively(see the ferrule 2200 e of FIG. 56). The recess portion 226 e, 226 f maybe formed to both ferrules which are brought into contact with eachother. Depending on the shape of the recess portion, the front endportions may be unintentionally engaged with each other by a rotation ofthe ferrules. However, by applying the fan shaped recess portion 226 f,the unintentional engaged state between the ferrules may be preventedeven if the ferrule rotates and the connection is made through the frontend surface.

As illustrated in FIG. 56, the front end of the ferrule 2200 e (or theferrule 2200 f) which is provided with the recess portion may be broughtinto contact with a front end of a normal ferrule which is provided withno recess portion. With the above-described structure, the electricalconnection between the ferrules may be established with reliabilitywhile the optical fiber may be prevented from being damaged by buttingthe end portions of the optical fibers with each other.

The optical connector apparatus according to first to the eighthembodiments explained above are used for the connection of theelectro-optical composite cable. However, the above-described conceptmay be applied to an optical connector apparatus which is used simplyfor connecting the optical cable.

DESCRIPTION OF NUMERALS

10, 10 a, 10 b, 10 c, 10 d optical connector apparatus

100 first electro-optical composite cable (electro-optical compositecable)

100′ second electro-optical composite cable

110 first optical fiber (optical fiber)

110′ second optical fiber

120 first protection cover (protection cover)

120′ second protection cover

121 optical fiber strand

122 tensile-strength resistant fiber

130 first metal conductor (metal conductor)

130′ second metal conductor

140 first outer jacket (outer jacket)

140′ second outer jacket

200 first connector (connector)

200′ second connector

202 first connector housing (connector housing)

202′ second connector housing

203 front end surface

204, 204′ lock portion

205, 205′ lock release portion

206 first bias member (bias member)

206′ second bias member

207 first cable stopper (cable stopper)

207′ second cable stopper

210, 210 a, 210 b, 210 c, 2100 main body portion

211, 211 a, 211 b, 211 c, 2110 wiring portion

212 first tubular potion (first adjuster portion)

212′ second tubular potion (second adjuster portion)

212 a tubular portion (first tubular portion)

226 a tubular portion (second tubular portion)

2200 a, 2200 b, 2200 c, 2200 d, 2200 e, 2200 f ferrule

220, 220 a, 220 b, 220 c first ferrule (ferrule)

220′, 220 a′, 220 b′, 220 c′ second ferrule

221, 221′ connected portion

222, 222′ front portion

223 bevel portion

224, 224′ back portion

225, 225 a, 225 c, 225 e, 225 f front end surface

226 e, 226 f recess portion

227 pushed surface

228 large diameter portion

229 hole

230, 230′ shoulder portion

232, 232′ ring-like recess

233 contact surface

240, 240 b, 240 c first sleeve (first crimped portion)

240′, 240 b′, 240 c′ second sleeve (second crimped portion)

500, 500 a adaptor

505 projection

510, 510 a adaptor housing

512, 512′ lock hole

520, 520 a, 520 b, 520 c, 520 d, 520 e connection member

521 cut portion

522, 522 d main body portion

523 slit

524 opposed-edges portion (joint portion)

525 a, 525 b, 525 c ferrule-contact portion

526 cut

527 receiving portion

528, 528 d, 528 e spring portion

529 support portion

530 first part

532 first insertion opening

534 second insertion opening

540 second part

541 edge portion

541 e conductive portion

550, 550 a accommodation portion

551 press-fit portion

552 support portion

554 accommodation space

554 a, 554 b end portion

560 fixing portion

800 optical element

801 terminal

802 installation surface

810 housing

812 joint-end surface

820 connection portion

900, 900 a adaptor

910, 910 a housing

926 cut

927, 927 a receiving portion

928, 928 a spring portion

930, 930 a connection member

941 end portion

941 a conductive portion

950, 950 a accommodation portion

951 press fit portion

952 support portion

954 a, 954 b end portion

960 element-accommodation portion

970 extended-connection portion

1. An optical connector comprising a first ferrule having a first endsurface and a second ferrule having a second end surface, wherein thefirst ferrule is provided with a first conductive portion, the secondferrule is provided with a second conductive portion, and a distancebetween the first end surface and the first conductive portion isdifferent from another distance between the second end surface and thesecond conductive portion.
 2. The optical connector as recited in claim1, wherein the first ferrule comprises a first end portion having acircular cylinder-like shape, the first end portion having a first outerperipheral surface and the first end surface, the second ferrulecomprises a second end portion having a circular cylinder-like shape,the second end portion having a second outer peripheral surface and thesecond end surface as an end surface, the first conductive portion isformed on at least a part of the first peripheral surface, and thesecond conductive portion is formed on a part of the second peripheralsurface, the location of the second conductive portion being distinctfrom the second end surface.
 3. The optical connector as recited inclaim 2, wherein the first conductive portion is formed on the entirepart of the first peripheral surface.
 4. The optical connector asrecited in claim 2, wherein a part of the second peripheral surfacebetween the second end surface and the second conductive portion is madeof insulative material.
 5. The optical connector as recited in claim 1further comprising a third ferrule having a third end portion, whereinthe third end portion comprises a third end portion having a circularcylinder-like shape, the third end portion having a third outerperipheral surface and the end surface, the third conductive portion isformed on a part of the third outer peripheral surface, the location ofthe second conductive portion being apart from the third end surface,and a distance between the third end surface and the third conductiveportion is different from either the distance between the first endsurface and the first conductive portion or the distance between thesecond end surface and the second conductive portion.
 6. An opticalconnector apparatus comprising the optical connector as recited in claim1 and a connection member connected with the optical connector, whereinthe connection member at least comprises two grip portions havingconductivity, one of the grip portions grips the first conductiveportion so as to be electrically connected with the first conductiveportion, and the other one of the grip portions grips the secondconductive portion so as to be electrically connected with the secondconductive portion.
 7. The optical connector apparatus as recited inclaim 6 further comprising another optical connector as a mating opticalconnector, wherein the connection member is an adaptor which connectsthe optical connector with the mating optical connector.
 8. The opticalconnector apparatus as recited in claim 6, wherein the connection memberis a mating connector for the optical connector.